Whenever a thin film glove is worn for barrier protection either by medical personnel or for industrial purposes the gloves will become uncomfortable to the wearer after a short time. This is due to the fatigue associated with the resistance of the glove caused by an intrinsic character known as “lesser elasticity”, which is measured in terms of its modulus. A higher modulus glove material is less satisfactory for such gloves.
Gloves that are made from natural (polyisoprene) rubber have favorable feel and comfort properties. However, natural (polyisoprene) rubber is associated with potential allergen (which causes Type I allergy). In view of this allergenic property, natural (polyisoprene) rubber is generally not suitable for use in the manufacture of dipped articles, such as rubber gloves due to the adverse effect of natural (polyisoprene) rubber on the wearer.
The current trend is to use synthetic materials like nitrile rubber, polyisoprene, styrene butadiene rubber, butyl rubber and vinyl to produce dipped articles such as gloves. Over the past few years the volume of glove production using synthetic materials has increased substantially. However, nitrile rubber, styrene butadiene rubber, butyl rubber and vinyl are not able to provide the favorable feel and comfort of natural (polyisoprene) rubber. While synthetic polyisoprene can provide a favorable feel and comfort that is comparable to that of natural (polyisoprene) rubber, synthetic polyisoprene is very expensive and is not suitable for use in the manufacture of some articles such as thin film gloves, which are used in high volumes and discarded.
Polychloroprene is a synthetic material that has been found to exhibit a similar texture, feel and softness as natural polyisoprene. Polychloroprene differs from natural polyisoprene in that the methyl group at the 2-position of the isoprene monomer is replaced with chlorine. However, conventional polychloroprene is very expensive and processing of polychloroprene requires a high energy input. In addition to these problems, a higher film thickness and high level of curing chemicals (almost 3-4 times that of natural polyisoprene) is required. For at least these reasons, conventional polychloroprene is not preferred for use in the manufacture of some articles, such as rubber gloves and particularly gloves that are discarded after a single use.
Elastomeric compositions such as those described above have the potential for application in articles other than gloves. For example, dipped articles may be configured for use in medical applications such as surgical gloves, examination gloves, catheters, tubing, protective covering, balloons for catheters, condoms and like, or for use in non-medical applications, such as industrial gloves, laboratory gloves, household gloves, gardening gloves, electrical gloves, irradiation gloves, finger cots, weather balloons, clean room gloves for electronic industries, gloves for food contact and food processing and biotechnical applications and the like. New developments in this field may identify further applications for these types of dipped articles that have not yet been identified.
There is a therefore a need for alternative or improved dipped articles, including compositions for forming these articles and methods of manufacturing the articles.